<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>两列式布局</title>
    <style>
        *{
            margin: 0;
            padding: 0;
        }
        /* .container{
            display: flex;
        } */
        .aside, .main{
            height: 500px;
        }
        .aside{
            float: left;
            width: 300px;
            background-color: green;
        }
        .main{
            /* flex: 1; */
            background-color: red;
            overflow: hidden;/*BFC*/
            /* margin-right: 300px; */
            /* float: left;
            width: calc(100% - 300px); */
        }
    </style>
</head>
<body>
    <!-- 自适应的两列式布局 
        计一套布局，两列式布局  aside  300px ，剩下的交给main 
        左右
        侧边栏固定宽度，主栏宽度自适应
    -->
    <div class="container">
        <aside class="aside"></aside>
        <main class="main"></main>
    </div>
</body>
</html>